Contrary to popular bullshit propaganda, the popular U.S. rocket launches are all done by businesses, not NASA. NASA provides program management, mission design for their own payloads, and so on, but they were never in rocket-making business, ever. Both Apollo and Space Shuttle were managed by NASA, but designed and built by subcontractors. Launched too. NASA has more input into design of their science payloads, but even then it's design only, not manufacturing. That's done by subcontractors still.
The only difference between the "commercial" launches and those prior to that is the amount of NASA management involvement. From the business standpoint, nothing much has changed between the "noncommercial" and "commercial" launches.
The 'commercial' launches aren't on a cost-plus contract. Any cost overruns are eaten by the launch provider, NOT the taxpayer. Can't bring it in under budget? Too bad, partner, we have a contract and have no problem suing you to get our money back.